This invention relates to a novel 2-methyl-4-amino-5-aminomethylpyrimidine carbonate which is useful as an intermediate for producing vitamin B1, a process for preparing the same and a method of purification of 2-methyl-4-amino-5-aminomethylpyrimidine using the same. As a method for producing vitamine B.sub.1, there has generally be known the method in which vitamine B.sub.1 is synthesized from 2-methyl-4-amino-5-aminomethylpyrimidine, carbon disulfide and 2-acetylbutyrolactone, as described in Yakugaku Zasshi (The Journal of Pharmacology) 71, 720 1215 (1951).